Currently, laser alignment devices are widely used in fields such as building engineering, home decorating and the like. U.S. Pat. No. 4,031,629 issued to Paluck on Jun. 28, 1977, discloses a laser alignment device in which a motor drives a laser beam to rotate to form a planar laser beam, thereby forming a straight laser line onto a target surface. The main body of the '629 patent is adjusted manually to horizontal, with the indication of level float, to ensure the laser line is in level. In some laser alignment devices instead of using a motor part to drive the laser to rotate, a type of linear lens is used for passing through a laser to convert it into a planar laser beam. Such a structure simplifies the internal structure of the laser alignment device and reduces energy consumption. A so-called linear lens can convert a beam of laser into a planar laser beam. U.S. Pat. No. 6,914,930 issued to Raskin on Jul. 5, 2005, sets forth a plurality of embodiments of linear lens. Both U.S. Pat. No. 4,247,809 issued to Nessel on Jan. 27, 1981 and U.S. Pat. No. 4,751,782 issued to Ammann on Jun. 21, 1988 disclose an automatic leveling laser alignment device with an electronic slope sensing element, which may omit manual leveling and simplify its operation.
However, the laser alignment devices of the above patents can only form a laser line on a target surface in a fixed direction such as a vertical surface, which limits the use of laser alignment devices.
The present invention is provided to solve the problems discussed above and other problems, and to provide advantages and aspects not provided by prior laser alignment devices of this type. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the accompanying drawings.